最新免费av在线观看,亚洲综合一区成人在线,中文字幕精品无码一区二区三区,中文人妻av高清一区二区,中文字幕乱偷无码av先锋

RX4000V4 Datasheet

  • RX4000V4

  • RX4000(uITRON4.0) Basics User＇s Manual | User＇s Manual[02/...

  • 309頁

  • ETC

掃碼查看芯片數(shù)據(jù)手冊(cè)

上傳產(chǎn)品規(guī)格書

PDF預(yù)覽

CHAPTER 5 SYNCHRONOUS COMMUNICATION MANAGEMENT
5.6.5 Simplified priority order control rules
In the
碌
ITRON4.0 Specification, two kinds of priority control rules related to mutexes are prescribed: detailed rules
and simplified rules, of which the latter are used in the RX4000.
The priority order of tasks that use mutexes to perform synchronization is therefore as follows.
(When mutex is locked)
Whichever has the highest priority among the following.
鈥?/div>
The task鈥檚 base priority value
鈥?/div>
The same priority value as the task with the highest priority among tasks waiting to lock a locked mutex with
the attribute TA_INHERIT
鈥?/div>
The highest top priority among locked mutexes with the attribute TA_CEILING.
(After mutex lock is released)
When all the locked mutexes are released, a task鈥檚 current priority changes to its base priority.
5.6.6
Locking mutexes
A mutex is locked by issuing one of the service calls loc_mtx, tloc_mtx, or ploc_mtx.
If there is a mutex lock request, the kernel checks whether that mutex is already locked by another task. If the
mutex is not locked by another task, the mutex can be locked by the requesting task. At this time, if the target mutex
has the attribute TA_CEILING, the current priority value of the task is raised to the top priority value of the mutexes. If
the mutex is locked by another task, the requesting task is put in the waiting state and registered in the waiting task
queue of the mutex. The order in which tasks are registered in this queue is FIFO order if the target mutex has the
attribute TA_TFIFO, and priority order if the mutex has one of the other attributes TA_TPRI, TA_INHERIT, or
TA_CEILING. Also, if the mutex has the attribute TA_INHERIT and the current priority of the waiting task is higher
than that of the task locking the mutex, the latter task鈥檚 priority is changed.
Note that when tloc_mtx is issued, the is released from waiting if the mutex cannot be locked within a specified
time. Note also that a mutex cannot be locked by processing units other than tasks.
5.6.7
Releasing mutex locks
A mutex lock is released by issuing the service call unl_mtx.
If a mutex lock is released when there are tasks waiting, the task at the top of the waiting task queue locks that
mutex. At this time, if the mutex has the attribute TA_CEILING, the priority value of the task newly locking the mutex is
changed to the top priority value of the mutexes. If the mutex has the attribute TA_INHERIT, because the task queue
has already been sorted into priority order, the priority of the task newly locking the mutex remains unchanged.
Note that if all mutexes being locked by a task are released, the task鈥檚 priority changes to its base priority.
5.6.8
Obtaining mutex information
Mutex information such as the ID number of a locked task can be obtained by using the service calls ref_mtx and
iref_mtx. For details of each service call, refer to
CHAPTER 13.
66
User鈥檚 Manual U14833EJ2V0UM

RX4000V4相關(guān)型號(hào)PDF文件下載

  • 型號(hào)
    版本
    描述
    廠商
    下載
  • 英文版
    RX4000(uITRON4.0) Basics User＇s Manual | User＇s Manual[02/...
    ETC
  • 英文版
    RX4000(uITRON4.0) Basics User＇s Manual | User＇s Manual[02/...

您可能感興趣的PDF文件資料

掃碼下載APP，
一鍵連接廣大的電子世界。

在線人工客服

買家服務(wù)：
賣家服務(wù)：
技術(shù)客服：

0571-85317607

網(wǎng)站技術(shù)支持

13606545031

客服在線時(shí)間周一至周五
9:00-17:30

關(guān)注官方微信號(hào)，
第一時(shí)間獲取資訊。

建議反饋

聯(lián)系人：

聯(lián)系方式：

按住滑塊，拖拽到最右邊
>>
感謝您向阿庫(kù)提出的寶貴意見，您的參與是維庫(kù)提升服務(wù)的動(dòng)力！意見一經(jīng)采納，將有感恩紅包奉上哦！